Can you be more specific, how long it's been? Days or weeks?
There are many reason a casino can hold funds and ask for KYC and further documentation, if they suspect of money laundering the the probable document that you need to provide is source/proof of funds.
According to the OP's statement, he said this has been over a week, which is more than two call days, and from the image of a member quoted above, I think the reason why the account was flagged was already identified, but the OP is not getting any reasonable response from them asking for any further information, which he's ready to provide to prove he's genuine.
I understand the OP's frustration; there is nothing as painful as not knowing when your case will be attended to. Since the casino has been promoted here on the forum, it will be easier to reach them either through their representative or the campaign manager.
In that case, it's not a normal verification, probably the KYC team is doing manual check to find the authenticity of the submitted documents which can take a while but not a week. But OP can wait for a while to see whether he receives anything from their ANN here instead of bombarding the same issue on the multiple threads which is not gonna make the procedure any faster.